1. Field of the Invention
The present invention relates to an organic EL display device and a method of manufacturing an organic EL display device.
2. Description of the Related Art
In recent years, an image display device (hereinafter referred to as an “organic EL display device”) using a self-luminous body called an organic light-emitting diode has been put to practical use. Since the self-luminous body is used, the organic EL display device is superior in terms of visibility and response speed compared to a related-art liquid crystal display device, and in addition, a further reduction in thickness is possible in the organic EL display device because an auxiliary lighting device such as a backlight is not necessary.
JP 2009-295911 A discloses that a peripheral portion of a planarization film composed of an organic material is covered, outside a display area, with a charge transport layer including any one of an alkali metal and an alkaline-earth metal to thereby suppress the entry of moisture or gas into an organic layer.
In the organic EL display device, an upper electrode, which is one of two electrodes, upper and lower electrodes, that interpose an organic layer including a light-emitting layer therebetween, is an electrode covering the entire surface of a display area in which the organic layer is formed, and the upper electrode is formed from a transparent conductive material. The upper electrode is connected to a wire outside the display area. For performing the connection outside the display area, a vapor deposition step or the like using a vapor deposition mask is performed in a manufacturing step so as to prevent the organic layer, which is deposited before the upper electrode, from being vapor-deposited outside the display area. However, a vapor deposition mask requires highly accurate processing, is expensive, and needs to be regularly cleaned and exchanged. Therefore, the vapor deposition step using a vapor deposition mask increases the number of man-hours of work, leading to an increase in manufacturing cost.